Kh and alk?

I have had a few fish acting weird and have not tested in along time(probally 6-8 weeks) I usually see tell tale signs that the tank is off. I just lost my 2 true perks for no reason and then tonight my sailfin was upside down dead? I did a full test the mag is 1400 the cal is 420 ph 8.0 the alk was low and the kh is 6-7 I guess my question is why is the mag or cal not off too? I thought these all went hand and hand? Is there a way to bring this up as I think that this is the cause for the dead fish. CAn allk low and kh low kill fish? I know its bad for the inverts but I thought the fish were better off. How do I reaise these? I did a full test and am repeting mag as I think it was actually 1280. I tripple checked the kh and it was turning between 6-7. I also retested the alk and it was very low. Please shoot some help

 

Anyone?

 

mine was the same way . didnt check for awhlie. i did a 1/3 water change in my 180 gal . alk came right back up cal went up alittle so did ph . was 8.0 to 8.3

 

Get some buffer and add slowly. You should test at least every other week. the little bit of time is worth saving the livestock.

 

AFAIK alkalinity does not affect fish except due to the fact that alk affects PH. Have you tested your PH?

I would assume that there are other issues. Have you tested ammonia/nitrites/nitrates?

 

Amonia is 0 nitrites are 0 and nitrates are 25 ppm the ph as stated is 8.0 kh is 6-7 and I guess it makes no sence. I have been doing good water changes regulary so I got out of the routien of testing as it was always the same. I guess now I learned my lesson.